i'm having some trouble with the nvidia drivers on my laptop that i can't seem to figure out. i've successfully used the drivers on many machines before, but to no avail this time. the laptop is a dell precision m50 with a new, updated fedora core 3. it has a Quadro4 550 GoGL card in it and a 1600x1200 dfp display.

previously, i was able to use this machine with hardware acceleration, with redhat 7.3 (XFree86 4.3 i think) and a 4xxx series driver, but i needed to upgrade for better firewire / usb support.

now, with fedora core 3, the nv driver works fine. i specify

HorizSync 29 - 80
VertRefresh 0 - 70

and from Xorg.log see that the dot clock's range is 12 - 350. it selects a modeline for 1600x1200 with a dot clock of 162MHz, a horizsync of 75KHz and a vertrefresh of 60Hz. this works perfectly.

when i switch to the nvidia driver making only the minimal changes to the xorg.conf file ('nv' -> 'nvidia' and disabling dri), the display is funky, with a 1024x768 desktop contained in a 1024x768 subrectangle of the display - outside this rectangle are randomly colored vertical lines. looking at Xorg.log, the 1600x1200 line was invalid, because the EDID values set the horizsync to 29 - 65 and the vertrefresh to 0 - 60, and the 1600x1200's horizsync is out of range.

i thought setting IgnoreEDID would fix the problem, since the old modeline works on this display. and in fact, the driver does successfully select the same 1600x1200 modeline, but the display is again funky - this time, the entire 1600x1200 desktop is squashed vertically in half and presented twice, once on the top half of the screen and again on the bottom. really, it looks like an interlaced signal is being displayed on the screen, but interlacing is not set in the modeline, and i didn't think DFP's needed / supported interlaced signals.

attached is an nvidia bug report (i had to gzip it because it was just over 100kb, but rename it to .log so the forum would accept it) from a test with the nvidia driver 8174 and IgnoreEDID set, showing it select the 1600x1200 modeline, but the display is definitely not correct with these settings.

hey, fantastic, that does work! i thought i'd tried that before, but i guess i didn't do it right. just for the record, i added the line

options nvidia NVreg_Mobile=0

to the end of /etc/modprobe.conf and then did an 'rmmod nvidia && modprobe nvidia' and was able to start up just fine! btw, this also works for me with driver 8174, but i had to set IgnoreEDID - have you tried that?

hey, fantastic, that does work! i thought i'd tried that before, but i guess i didn't do it right. just for the record, i added the line

options nvidia NVreg_Mobile=0

to the end of /etc/modprobe.conf and then did an 'rmmod nvidia && modprobe nvidia' and was able to start up just fine! btw, this also works for me with driver 8174, but i had to set IgnoreEDID - have you tried that?